Abstract: The multiple zeta values can be thought of as homomorphic images of a certain subset of the quasi-symmetric functions QSym. By considering the power series for the logarithmic derivative of the gamma function, one sees a natural extension of this homomorphism to all of QSym, which can be restricted to a homomorphism from the symmetric functions to the reals. We shall discuss the effective computation of this latter homomorphism using some ideas from combinatorial Hopf algebras, and its applications in topology.